


We Need To Test These Suckers Out

by indigomini



Series: Tentacles Kaisoo [1]
Category: EXO (Band)
Genre: Alternate Universe - Harry Potter Setting, Double Penetration, M/M, Magical Accidents, Tentacles
Language: English
Status: Completed
Published: 2016-12-29
Updated: 2016-12-29
Packaged: 2018-09-13 03:43:47
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,894
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/9105154
Author URL: https://archiveofourown.org/users/indigomini/pseuds/indigomini
Summary: Kyungsoo works in the Department of Performance Enhancing Magic Research for the Ministry of Magic. He has to test a swimming enhancement spell today, but his test subject is distracting as hell.





	

The Ministry of Magic has possibly an innumerable amount of departments, with new ones spawning daily. Kyungsoo's position is in the Department of Performance Enhancing Magic Research, which is an offset from the Office for the Detection and Confiscation of Counterfeit Defensive Spells and Protective Objects. It’s actually quite a sweet gig, since his job consists of researching and testing spells and potions that would, as the name states, enhance performance, be it in athletics, mental acuity, or—ahem—sexual performance. (Although,  _ really _ , who needs to go beyond an Engorgio charm, is what Kyungsoo always says.) His job is to test for safety and put out bulletins if his findings deem something unsafe for public consumption.

Today should be fun. He is testing a recipe for a potion that is suppose to enhance agility in swimming. Some members of the national swim team got caught with it during practice, and have been shelved until further notice. Technically, there are no rules against transfiguration, which is what the spell seems to look like, so long as it is not a full body shift. Its legality is up for question, so Kyungsoo is going to determine if it will be allowable.

Today should  _ definitely _ be fun, because the test subject for this experiment is none other than Kim Jongin. As in the Kim Jongin with the luscious lavender hair, golden skin, pouty lips, and  _ godly _ body proportions. The one with legs that don’t quit and an ass that Kyungsoo would gladly feast on until the end of his days.  _ That _ one. Kyungsoo has something of a crush on him.

He hears Jongin arrive when he’s in the middle of adding ingredients to the cauldron. The boy is standing to the side, patiently waiting for instructions. He flashes Kyungsoo a blinding smile, and Kyungsoo swears he feels his heart skip a beat. Hot damn, he’s so pretty.

“Good afternoon, Mr. Do,” Jongin says, earning himself a scowl in return.

“Just Kyungsoo,” he corrects. The boy just graduated, but it’s not like Kyungsoo was knocking on death’s door. He was only a couple of years older at most. He’s even had to start hiding away his jacket and tie on days Jongin is scheduled so he can look more casual. It’s enough that he has such lewd thoughts about the boy, he doesn’t need to feel like an old pervert on top of it.

“Sorry.  _ Kyungsoo _ ,” Jongin says with a smirk. Sometimes, Kyungsoo swears he knows just what he’s doing. Oh man, the way his name sounds coming out of Jongin’s mouth though… “What do you need from me today?”

Oh, right. Work. “Ahh…” What was he doing? Oh yeah. “We’re going to test some swimming enhancers. I’ve got the Research Room set up with a pool, but this potion needs another half hour to cook. Here’s the waiver. You can read over it, get changed, and meet me there.”

Yeah, about that. He totally booked Jongin for this so he could see him in a tight, tiny Speedo. Kyungsoo would feel guilty, but really...no, he doesn’t.

Jongin wanders back to find the researcher just as he was adding the finishing touches to the potion. He has a small towel wrapped around his hips, and all the tanned skin of his perfect, bare chest and limbs were distracting as hell. Kyungsoo doesn’t even catch what Jongin asked.

“Sorry, what?”

Jongin arches an eyebrow, looking somewhat amused until he remembers why he came. “I was just checking on you...and I wanted to see if it was necessary that I wear this swimming suit or if I could just get some trunks?”

Hell, the amount of skin he was showing was enough to power some  _ damn _ fine fantasies for weeks, but… “Well, that’s the standard issue uniform for the swimmers, and we want to control as many variables as possible,” Kyungsoo finds himself saying. Self high-five, bullshit game on point.

“It’s just,” Jongin says, shyly pulling the towel open, and Kyungsoo could almost hear his jaw hit the floor. “It’s  _ really _ small?”

“If that’s what you call small…”

Silence. Kyungsoo looks up at his face. Jongin purses his lips to hide a smile and clears his throat. “I-...the  _ swimsuit  _ is kind of small…”

“Right!” Kyungsoo says too loudly. “Well, they have like...thongs and stuff for swimwear, you know. Now... _ those _ , those are tiny. But this is just right. It’s nice and thick-”  _ Fuck _ . “-...fabric, and girth-”  _ Goddammit _ . “...Good coverage.”

Jongin, bless his heart, looks a little lost amidst Kyungsoo’s word vomit. He must have just gotten the takeaway message that he has to wear it after all and nods, quietly turning on his heels to head to the Research Room. Kyungsoo watches him go, feeling an irrational urge to pet his fuzzy legs, and eventually scraping his jaw off the ground.

The potion. Not a problem. This is Kyungsoo’s specialty, after all, and it’s a simple incantation. He reads it off as he stirs the cauldron, letting his mind wander back to the bulge in the tight red briefs. The viscous liquid flashes a brilliant blue, which is...interesting. The way the potion was written, Kyungsoo had assumed it’d be more of a violet, but it’s not like these things came standardized and with a wealth of research to back it up. Whatever. He distills it into a small shot glass, grabbing it too quickly and having to hot potato it between his hands.

Jongin has his hands in his lap and his legs in the pool when Kyungsoo steps into the room. He starts to get out, but the elder just waves him off and walks faster. The glass has cooled down enough, and Jongin looks down at it, sneering in disgust.

“One day, they’ll make a potion that actually looks drinkable,” he says, taking the glass and eyeing it miserably.

“Sorry,” Kyungsoo answers, crouching down next to him.

“Not your fault,” Jongin murmurs, holding the glass against his lips. “Bottoms up?”

“Yep. Probably fast too. It looks sour.”

Jongin grimaces, but throws it all back dutifully. Kyungsoo stares as his Adam’s apple bobs, his gaze trailing down Jongin’s chest to his lightly defined stomach, and the trail of hair leading down…

“ _ Yuck _ ,” the boy says, setting the glass down next to him. “Tastes like raw squid gone bad.”

Kyungsoo scrunches his nose in response, pulling out his quill and jotting down the time on his clipboard, along with some notes. “Gross. Tastes...like...bad squid…” he says, scribbling it down on the ledge.

“So what’s supposed to happen?” Jongin asks.

“Your legs are gonna transform. We need to track time and how far up it extends,” Kyungsoo answers.

“How far up?”

“Well, the rules currently are if fifty-one percent of the swimmer is still in fully human, unenhanced form, then it’s fine.”

“Oh, so that’s why I needed to wear the speedo.”

Yeah...that’s totally why...

Jongin’s stomach gurgles. “Ow…”

“You okay?”

“Yeah, I just feel—” He rubs at his lower abdomen. “Ugh, can I get some water?”

“We’re really not suppose to let you have anything after the experiment starts…” Kyungsoo says, but he’s already standing up. Whipped. “You can have a small sip though, okay?”

“Thank you,” Jongin says quickly.

Kyungsoo glances at the clock on the wall. It’s only been a minute or two. It’ll be fine. He walks back to his office to grab a water bottle, and nearly drops it when he hears a shrill screech. He’s rushing back to find Jongin hunched over, his arm spasming in his lap. “Hey! Hey, are you okay?”

“Ahh,  _ help _ !” Jongin cries, trying to pull his arm back.

Kyungsoo pushes the boy upright and his eyes turn into saucers at the sight before him. A blue tentacle was creeping out of the top of Jongin’s swimsuit, latching onto the boy’s wrist and tugging. Kyungsoo reaches down instinctively to bat it away and Jongin folds back in half, groaning in pain as his arm falls to his side.

“Crap, are you okay? What happened?” Kyungsoo asks. “I was gone for like less than a minute!”

“It feels like you just slapped me in the balls,” Jongin moans.

Kyungsoo looks down at the boy’s legs. All human. No changes. “Sit up?”

The boy does so carefully, wincing as he straightens up. The tentacle was still over the fabric, twisting in the air. Another one poked out from one of the leg holes. It’s attached itself to Jongin’s thigh.

“Oh crap, oh crap…” Kyungsoo mutters, and he had imagined saying this under very different situations: “Take off the swimsuit. We have to see what we’re dealing with here.”

Jongin lets out a pitiful whine, trying to avoid the tentacle and stretching the waistband out. Two more swirl up, much bigger than the previous ones. The suckers were more prominent, with a rosy outline around each versus the solid blue of the smaller two.

“I don’t think this was suppose to happen,” Jongin moans out, trying to wrestle his hand away from one of the larger tentacles that had managed to snag two of his fingers. It stretched out for quite a bit before Jongin’s fingers broke free, and he doubles over again.

“Does it hurt? Do you need help?”

“ _ Yes _ , I need help!” Jongin snaps. “I think this ate my penis! Or it  _ is _ my penis, I don’t even know!”

“But does it  _ hurt _ ?” Kyungsoo repeats. He needs to assess.

“No. Just from when you hit that one,” Jongin says, pointing warily at the skinny one still circling, like  it was tasting the air for prey. “But it doesn’t anymore.”

“Okay…” Kyungsoo says. “Okay, stay here. Let me look at the recipe again. I’ll be right back. Yell if anything changes, okay?”

“You’re going to  _ leave  _ me?” Jongin says, looking panicked and latching onto his arm. “Don’t leave me!”

“Just for a second. I’ll be back, I promise.”

—

So...Kyungsoo  _ might  _ have switched up the proportions of some ingredients. He also might have...possibly chanted a word or two wrong in the incantation. The problem with hodge-podged, homebrewed spells is sometimes there’s no room for error. It must be replicated to the letter, or there could be  _ dramatically  _ different results.

He goes back to the room, recipe in hand, to find Jongin had pulled the swimming briefs down and was now experimentally...communicating with one of the tentacles. He holds an index finger out, and Kyungsoo watched as the tentacle curves and narrows its tip to slowly reach forward and touch it.

“What are you doing?” Kyungsoo asks, causing Jongin to break concentration with a surprised shout, and the tentacle wraps around his wrist and contracts in response.

“Agghhh,” Jongin says, fighting with it for several seconds before he stops to take in a deep breath. Kyungsoo watches as it slowly releases his arm, the flat suckers making soft popping noises as they part from his skin. “I...I can control it. So...it’s  _ me _ . It’s  _ weird _ , but it’s basically like fingers.”

Kyungsoo says nothing, staring in fascination.

“What did you find?” Jongin asks, and the tentacles lift up toward him, as if expecting an answer too.

He can’t say it was his fault. That’ll ruin his chances forever. “The spell must have...issues.”

Jongin holds his hand out in front of him, and they watch together as two of the tentacles twist up, correcting their trajectory, and stretching to reach, eventually tapping against his fingertip. “Please tell me this isn’t permanent,” he whines softly.

“It’s not,” Kyungsoo says. “It should only last like...an hour or two.” Maybe.

Jongin lets out a long, sad sigh, staring down between his legs.

“Ca- Can I touch one?”

“What?”

“They’re dexterous, and we have to wait it out anyway,” Kyungsoo rushes out. “We can...we can still proceed with the experiment. I can still take notes.”

Jongin doesn’t believe a word of it, Kyungsoo can tell by the look on his face. He’s going to storm out here with his cool new freaky deaky—

“...Sure.”

“Whah?”

“Go ahead,” Jongin confirms, leaning back and sulking at them. “Do you need me to do anything?”

“Don’t think so…” Kyungsoo replies absently, holding a hand out above them like Jongin did. He can see Jongin tense up his stomach, flexing, and one of the bigger ones reaches up. It touches his palm, and he closes his fist around it instinctively. Jongin’s mouth forms an ‘o’ and he makes a small, surprised sound. It’s not squishy, like he had expected. Kind of spongy, the end tapering off into a thin spiral. He gives it a careful squeeze, and Jongin lets out what is unmistakably a moan of pleasure. One of the smaller tentacles attaches to his wrist and pulls it downward. Kyungsoo lets it guide him, watching as he strokes down the slick flesh and feeling it firm up under his fingers.

“Sorry,” Jongin says, his voice low. He was starting to breath heavily. “I...I can’t control it that well.”

Kyungsoo lets go of the first one, and can see out the corner of his eye Jongin biting his lip and looking away, flushing from embarrassment. He grabs onto the other big one and repeats the motion, pulling a confused moan from the boy.

“Why four though…” Kyungsoo mutters, spreading his fingers out and playing with the smaller two.

“ _ Ohh _ … What?” Jongin asks, his mouth falling open.

“You have these two smaller ones,” Kyungsoo points out, letting them spiral around his fingers briefly before pulling away. They comply much better than they did with Jongin. He reaches for one of the larger ones, and the second tentacle pushes its way into his palm greedily, coating it with clear slick. “And then these two bigger ones,” he murmurs, stroking both in his hand, feeling little ridges raise on their undersides and watching as Jongin’s hips jerk. “Shouldn’t there be like...just one big one? Or three?”

“I don’t know,” the boy rushes out, moaning afterward.

“Do they all feel the same? Is it the same level of sensitivity?” Kyungsoo finds himself asking. He’d be impressed with how professionally he’s handling this if he wasn’t jerking off an experiment gone wrong and sporting a raging boner from it.

“ _ Ahhh _ , I don’t know, Mr. Do, please stop!” Jongin squeaks out, gritting his teeth.

Kyungsoo lets go instantly, his eyes going wide as reality set in. Oh no. “Sorry. I’m so sorry. That was...really inappropriate of me.”

Jongin lets out a long, shuddering exhale through his mouth, shaking his head. “No,” he says. “I-...I was about...to…”

_ Oh. _ The boy hides his face behind his hands. Kyungsoo looks back down to see the two bigger ones had swelled up to where they stood straight, swaying from the movements of the other two. “You’re supposed to stop calling me that.”

Jongin peeks out from between his fingers. “Sorry. Kyungsoo,” he says, although not nearly as confident as he did earlier today.

“Do you not want me to touch you?” he asks bluntly.

“No, I  _ do _ ,” Jongin says, dropping his hands to his lap only to have them grabbed by the tentacles and he yanks away in frustration. “...I like you,” he mumbles.

“What?” He may be of age, but their relationship is volunteer test subject and evaluator. This is shaky territory.

“I liked it?” Jongin says, looking away.

“Did you like it or do you like me? Which one is it?” Kyungsoo presses.

The boy licks his lips nervously, chancing a glance up at Kyungsoo’s face. “...Both?”

“Are you sure?”

“...Yes?”

Kyungsoo stares down at Jongin’s lap, chewing on his lower lip in thought. A quick glance at the clock reminds him that they’re about half an hour into the trial. He reaches for the tentacles again, enjoying the feeling of the suckers attaching and then popping off of his fingers as he flips his palm back and forth. The smaller ones come up as well, rubbing the webbing between his fingers. It tickles. “In what way do you like me?” he asks.

“Well,” Jongin says, his tongue darting out over his lips again, weighing his options. “I’ve been kind of hoping you’d fuck me one of these days.”

“And one of these days, I will,” Kyungsoo promises, gently wringing one of the thicker tentacles and watching clear slick ooze out the tip, pooling in his hand. “But today, we need to test these suckers out.” Literally.

“These?”

“For science.”

“Like…” Jongin says slowly, a bewildered expression on his face. “Like fuck you with them?”

“Don’t think you can do it?” Kyungsoo challenges. That did the trick, going by the determined set in the boy’s jaw.

Jongin pushes his hand away and rolls over to kick his tiny swimming briefs off the rest of the way, letting them fall into the water behind him. The blue appendages are pointing straight out at Kyungsoo, bobbing in tandem at the slightest motion. He’d question it, but Jongin’s arms bracket his hips, and all the elder is thinking about is how to hurry this along already, fumbling with the buttons of his shirt as Jongin reaches for his zipper. 

The boy has Kyungsoo’s legs in the air as he tries to yank the pants and underwear all the way off when Kyungsoo feels something probing at his ass. He can see Jongin still struggling to get his pant legs over his shoes, but he looks down in time to watch one of the bigger tentacles spiral itself around his hardening length just as the two smaller ones press against his entrance and pry it open.

“You’re gonna miss it if you keep fucking around,” Kyungsoo moans out as the shiny blue tentacle springs back and forth over his pale pink shaft, jerking him off. The color contrast actually looked quite pretty. He lets out a groan as the lower ones push past his rim and spread apart, stretching him open, curling inside him.

“I-  _ dammit- _ ” Jongin grunts out in frustration as he glances down. He gives Kyungsoo’s pants one last yank on each leg and they finally comes off, taking his shoes with them. “Oh wow…” he breathes out.

“What does it feel like?” Kyungsoo asks, although any semblance of a scientific study has long passed. His back arches as pleasure spikes suddenly. They were rubbing right up against his prostate, and it made his face tingle with each drag.

“You feel so good,” Jongin rushes out, and that’s not what he asked, but the smaller tentacles retract as Jongin pushes the remaining large one in, stretching him further. It’s gradual, easy enough for him to take, and each rough ridge creates a quick vibration against his entrance.

“Ahh  _ shiiit _ ,” the elder keens out, feeling suction around the fullness inside of him. The other ones had attached to his rim, suctioning and sliding like an eager pair of tongues. The one on his dick was still going, its tip tracing along the underside of the head.

Jongin is already panting by the time he starts pumping into him, the tentacle now rigid to glide in smoothly, but still managing to flick at his sweet spot with every thrust in. Kyungsoo wonders absently as his whimpers climb in pitch if it’s four times the sensation for the boy. It’d only be fair, since he’s overwhelmed with all the stimulation at once right now. 

Kyungsoo pushes away the one stroking down his own length. “This one too,” he breathes out.

“What?” Jongin offers intelligently, eyes widening.

“Put it in me,” Kyungsoo clarifies, growing impatient. He’s embarrassingly close already, and he doesn’t want it to be over that fast.

Jongin’s hips slow down just enough for him to focus, bringing the tentacle down to wrap around Kyungsoo’s balls, pressing into his perineum, as the two smaller ones join the one in his ass, spiraling together and scissoring him open more. It aches, and he’s  _ so full _ already, but he’s  _ determined _ . The small ones withdraw and within moments, Jongin is lining the second large one up, squeezing it in alongside the orher.

“Ahhh...” Kyungsoo moans out, embracing the initial burning sensation, letting it distract him from his building orgasm. “Oh  _ fuck _ , that’s so big… Ah, it’s so  _ big _ ,” The pressure was so intense, he forgot to breathe for a moment, gasping for air and welcoming the tendril that wrapped back around the base of his cock as Jongin started rolling his hips forward again.

The ridges must be getting more pronounced, or maybe he was just stretched to the brink, but each ribbed line that bumped past his rim practically vibrates through him. They were twisting around each other inside of him, suckers grazing his prostate as they slid past. It was still too much. He watches Jongin’s eyes glaze over briefly, his mouth dropping open in surprise as his thrusts fall out of rhythm, and a shiver runs down his body. 

Kyungsoo looks down past his leaking cock with a tentacle still suckling along it, but all he could see were the two thick appendages being stuffed into his hole.

“Where’s Little Lefty?” Kyungsoo grunts out softly, trying to lift himself up to see further.

“It’s- it’s in my ass- I didn’t-  _ ahh _ ,  _ Kyungsoo _ ...” Jongin says, his eyes rolling back. It must be hitting somewhere nice. His hips buck forward, and his moans grow more frantic as he starts hammering so deep into Kyungsoo, the elder was seeing fireworks explode behind his eyelids with each thrust.

Jongin’s hand wraps around Kyungsoo’s dick, pushing the tentacle down to grip around the base as he strokes right under the head, rolling the loose skin over the ridge and jerking in short, rough pumps, whimpering out his name repeatedly. Kyungsoo feels a warm rush along his walls as the tentacles spasm inside him, and wetness landing on his skin as he sees the one around his dick spurt hot cum onto his thigh. Some hit his stomach, and he realizes  _ he’s  _ orgasming, feeling lightheaded and detached and watching as his cock twitches and dribbles out more white droplets before Jongin collapses on top of him.

It takes them several minutes to get their breathing under control. He had to push Jongin off of him after the first one or risk asphyxiation, feeling the suckers detach from his flaccid length and the cum leaking down his ass when Jongin pulled out of him. Kyungsoo was too thoroughly fucked out and tired to care.

“I  _ dreamt _ of this,” the boy beside him says after a period of silence. “But it was nothing like this.”

“Oh yeah?” Kyungsoo answers, voice barely audible. He was getting sleepy. “How d’you picture it then?”

“I thought you’d let me ride you on your desk.”

“That can be arranged.”

Basking was nice. The afterglow was nice. Kyungsoo could see out the corner of his eye the tentacles had gone back to skin colored and smoothing back out slowly.

“I think,” Jongin says after some thought. “I think they were flexible enough that I could ride you while still being able to fuck you…”

Kyungsoo lifts his head up weakly. “Wait, seriously?”

“I think so.” Jongin mutters.

“I made a large batch,” Kyungsoo says, feeling reenergized. “There’s a lot more.” Who wants an Engorgio charm when you can have tentacles?


End file.
